Air conditioner

ABSTRACT

An air conditioner ( 1 ) includes an air-blowing unit ( 4 ) and an air-conditioning unit ( 5 ). 
     The air-blowing unit ( 4 ) includes a fan case ( 9, 10 ) defining a pair of independent scroll chambers ( 6, 7 ), a pair of fans ( 9, 10 ) respectively provided in the pair of scroll chambers ( 6, 7 ). The air-conditioning unit ( 5 ) includes an air-conditioning case ( 13 ) defining an air passage (P) which air from the air-blowing unit ( 4 ) flows and air-conditioning components ( 14, 15, 17 ) provided in the air passage (P) and configured to condition air flowing from the air blowing unit ( 4 ) therethrough. A partition ( 25 ) partitioning a portion (P 1 ) of the air passage (P) from an inlet (P 0 ) to the most upwind air-conditioning component ( 14 ) into a pair of independent passages (P 1   a , P 1   b ) is provided. The pair of independent passages (P 1   a , P 1   b ) respectively communicate with discharge ports ( 6   b,    7   b ) of the pair of scroll chambers.

TECHNICAL FIELD

The present invention relates to an air conditioner, such as a vehicularair conditioner, including an air-blowing unit with a pair of fans, andan air-conditioning unit.

BACKGROUND ART

As a conventional art of an air conditioner, a vehicular air conditioneris disclosed in Japanese Patent Application Laid-Open No. 5-172100, forexample. The vehicular air conditioner includes an air-blowing unit 101and an air-conditioning unit (not shown) for conditioning air blown fromthe air-blowing unit 101, as shown in FIG. 10. The air-blowing unit 101includes a casing 104 having two parallely-provided scroll chambers 102,103, which have scroll centers matched to each other, and a pair of fans105, 106 respectively accommodated in the scroll chambers 102, 103, andan electric motor 107 for driving the fans 105, 106. When the electricmotor 107 is activated, the pair of fans 105, 106 rotate. When the fans105, 106 rotate, air is introduced from intake ports 108, 109 into thescroll chambers 102, 103. The air introduced in the scroll chambers 102,103 is discharged from the air-blowing unit 101 into theair-conditioning unit via a discharge port 110. The electric motor 107is supported by a partition wall 111 defining the scroll chambers 102,103. In both sides of the partition wall 111, porous bodies 114, 115 areprovided apart from the partition wall 111 and the spaces between thepartition wall 111 and the porous bodies 114, 115 are defined as airchambers 112, 113. Inside the discharge port 110 of the casing 104, arib 116 projecting from the partition wall 111 toward the air flowdirection is provided. According to this conventional art, noise, whichis generated when air from the pair of fans 105, 106 flow into eachother, is suppressed using the air chambers 112, 113, the porous bodies114, 115 and the rib 116.

DISCLOSURE OF THE INVENTION

However, according to the conventional art, the air discharged fromrespective outlets of the scroll chambers 102, 103 is to be flown intothe discharge port 110 (an inlet of the air-conditioning unit) which hasa remarkably larger passage cross-section compared to the respectiveoutlets of the scroll chambers 102, 103. This can cause a rapidreduction in flow rate, unevenness or a mutual interference of thedischarged air from the respective outlets of the scroll chambers 102,103. As a result, a resistance in the passage or noise can be increased.

The present invention provides an air conditioner that suppresses amutual interference of discharged air from a pair of fans.

A first aspect of the present invention is an air conditioner including:an air-blowing unit having a case defining a pair of independent scrollchambers, and a pair of fans respectively provided in the scrollchambers; and an air-conditioning unit including an air-conditioningcase defining an air passage which air flowing from the air-blowing unitflows through, an air-conditioning components provided in the airpassage and configured to condition air flowing therethough, and apartition partitioning a portion of the air passage between an inlet andthe most upwind air-conditioning component into a pair of independentpassages respectively communicating with the pair of scroll chambers.

A second aspect of the present invention is an air conditionerincluding: an air-blowing unit including a case defining a pair ofindependent scroll chambers, and a pair of fans respectively provided inthe pair of scroll chamber; and an air-conditioning unit including anair-conditioning case defining an air passage which air flowing from theair-blowing unit flows through, and air-conditioning components providedin the air passage and configured to condition air flowing therethrough.The air passage of the air-conditioning unit includes an introductionpassage between an inlet and a cooling heat exchanger as one of theair-conditioning components, a passage portion between the cooling heatexchanger and an air mixing door device provided downstream the coolingheat exchanger as one of the air-conditioning components, a hot airpassage provided downstream the air mixing door device and having aheating heat exchanger as one of the air-conditioning componentstherein, a bypass passage provided downstream the air mixing door deviceand not having the heating heat exchanger therein, and an air mixingchamber provided at a confluence portion of the hot air passage and thebypass passage to mix hot air and cool air. The air passage of theair-conditioning unit is partitioned into a pair of independent passagesthat respectively communicate with the pair of scroll chambers and aconfluence portion communicating the pair of independent passages isprovided between the cooling heat exchanger and the air mixing doordevice.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a portion in front of a passengercompartment including an air conditioner according to an embodiment ofthe present invention;

FIG. 2 is a sectional view of the air conditioner according to theembodiment of the present invention;

FIG. 3 is a sectional view taken along the line A-A in FIG. 2;

FIG. 4 is a perspective view of the air conditioner in which a portionabove the line A-A in FIG. 2 is removed;

FIG. 5 is a plan view schematically showing a relevant part of the airconditioner;

FIG. 6 is a diagram showing characteristics of noise level of the airconditioner during operation;

FIG. 7 is a sectional view of an air-conditioning unit of an airconditioner according to another embodiment of the present invention;

FIGS. 8( a) and 8(b) are diagrams showing characteristics of flow ratedistributions (vector) at a measured face along the line B-B shown inFIG. 7;

FIGS. 9( a) and 9(b) are diagrams showing characteristics of staticpressure distributions at the measured face along the line B-B shown inFIG. 7; and

FIG. 10 is a sectional view of a conventional air conditioner.

DETAILED DESCRIPTION OF THE INVENTION

An air conditioner according to an embodiment of the present inventionwill be described with reference to the drawings.

As shown in FIG. 1, an air conditioner 1 of the present embodiment isinstalled in an instrument panel IP in front of a passenger compartment2. In other words, the air conditioner 1 is housed between a dash panelDP and the instrument panel IP of the vehicle. The air conditioner 1includes an air-blowing unit 4 and an air-conditioning unit 5.

As shown in FIG. 5, the air-blowing unit 4 includes a casing 8 having acouple of scroll chambers 6, 7, which has scroll centers matched to eachother, a pair of fans (so called a twin fan) 9, 10 housed in therespective scroll chambers 6, 7, and an electric motor 12 for drivingthe fans 9, 10. The fans 9, 10 are centrifugal sirocco fans. Theelectric motor 12 is disposed between the two fans 9, 10. The electricmotor 12 has a drive shaft 11 serving as a rotating shaft to rotate thefans 9, 10 so that rotation of the drive shaft 11 of the electric motor12 rotates the two fans 9, 10.

As shown in FIG. 1, the air-conditioning unit 5 has an air-conditioningcase 13. The air-conditioning case 13 defines an air passage P therein.In the air passage P, a plurality of air-conditioning components 14, 15,16, 17 are provided to condition air passing through the air passage P.The air-conditioning components are an air filter 14 for collectingforeign particles contained in the air, an evaporator 15 as a coolingheat exchanger, an air mixing door device 16 and a heater core 17 as aheating heat exchanger.

The air passage P of the air-conditioning unit includes, in order fromupstream to downstream, an introducing portion P1 extending from aninlet P0 to the air filter 14 and evaporator 15, a portion P3 from theevaporator 15 to the air mixing door device 16, a hot air passage P5 anda bypass passage P6 provided downstream the air mixing door device 16,an air mixing chamber P7 at a confluence of the hot air passage P5 andbypass passage P6, and outlet passages P8, P9, P10 branched from the airmixing chamber P7. The outlet passages P8, P9, P10 are a defrosteroutlet passage P8 that opens toward a front window FW of the vehicle anda vent outlet passage P9 that opens toward passenger's upper body and afoot outlet passage P10 that opens toward the passenger's lower body.

The hot air passage P5 and bypass passage P6 are provided in paralleland downstream the air mixing door device 16. The hot air passage P5accommodates the heater core 17 as a heating heat exchanger. Incontrast, the bypass passage P6 does not have the heater core 17. Thus,when cool air from the evaporator 15 flows through the hot air passageP5, the air is heated and flown to the air mixing chamber P7 as hot airand, when cool air flows through the bypass passage P6, the air flows tothe air mixing chamber P7 simply as cool air.

The air mixing door device 16 adjusts the distribution ratio of the coolair from the evaporator 15 given to the hot air passage P5 and bypasspassage P6. The air mixing door device 16 is composed of a door case 16a and a sliding door 16 b slidably supported by the door case 16 a. Thedoor case 16 a has an opening (not shown) serving as an inlet of thebypass passage P6 and an opening (not shown) serving as an inlet of thehot air passage P5. When the sliding door 16 b opens the hot air passageP5 and closes the bypass passage P6, as shown in FIGS. 1 and 2, all coolair from the evaporator 15 is led to the hot air passage P5. On theother hand, when the sliding door 16 b closes the hot air passage P5 andopens the bypass passage P6, all cool air from the evaporator 15 is ledto the bypass passage P6. Further, when the sliding door 16 b partiallyopens both of the hot air passage P5 and bypass passage P6, the cool airfrom the evaporator 15 flows through the respective of the hot airpassage P5 and bypass passage P6. The hot air flown through the hot airpassage P5 and the cool air flown through the bypass passage P6 aremixed in the air mixing chamber P7 to provide air having a desiredtemperature.

The air conditioner 1 according to the present embodiment has, as shownin FIGS. 1 to 4, a partition plate 25 as a partition extending from theinlet P0 of the air passage P to the most upwind air-conditioningcomponent (the air filter 14, in this example) in the air flow directionin the introducing portion P1 of the air passage. The introducingportion P1 of the air passage P is thus partitioned into a firstindependent passage P1 a and a second independent passage P1 b. Further,the passages P5, P6, P7 downstream the mixing door device 16 arepartitioned into first independent passages and second independentpassages by a partition plate 26 as a partition extending in the airflow direction.

The space portion P3 between the evaporator 15 and mixing door device 16does not include the partition plates 25, 26 and the space portion P3serves as a confluence portion P3 where the right and left independentpassages P1 a, P1 b meet each other. Further, in the door case 16 a ofthe air mixing door device 16, a partition plate 16 c as a partition isprovided separately from the partition plate 26. The partition plate 16c is disposed on the same plane as the partition plate 26 as if thepartition plate 26 is continuously extended.

Here, the introducing portion P1 extends in a direction discharge ports6 b, 7 b of the scroll chambers 6, 7 extend and in a directionsubstantially perpendicular to the air flow directions in the evaporator15 and air filter 14. Thus, the introducing portion P1 extends along theflow direction of the air blown from the air-blowing unit 4 and the airpassing through the introducing portion P1 turns at a substantiallyright angle and flows in to the air filter 14 and evaporator 15.

Effects of the present embodiment will be described.

When the electric motor 12 of the air-blowing unit 4 is activated, thefans 9, 10 rotate. When the fans 9, 10 rotate, the air inside andoutside the passenger compartment 2 is introduced into the air-blowingunit 4 and sent to the air-conditioning unit 5 disposed downstream theair-blowing unit 4.

The air sent from the air-blowing unit 4 to the air-conditioning unit 5firstly flows through the introducing portion P1 of the air passage Pand foreign particles are removed as passing through the air filter 14.Then, the air cleaned by the air filter 14 is cooled by the evaporator15. The air cooled by the evaporator 15 flows into the air mixing doordevice 16 via the confluence portion P3. The air flown into the airmixing door device 16 is distributed to the hot air passage P5 or bypasspassage P6, mixed in the air mixing chamber P7 and provided in a desiredtemperature. The air having a desired temperature is blown from the airmixing chamber P7 into the passenger compartment 2 via desired outletpassages P8, P9, P10 according an open/close state of mode selectiondoors 18, 19, 20.

As described above, the air temperature is controlled in the air mixingdoor device 16. For example, a full foot mode can be selected when thesliding door 16 b closes the bypass passage P6 and opens the hot airpassage P5 (see FIGS. 1 and 2). On the other hand, a full cool mode canbe selected when the sliding door 16 b opens the bypass passage P6 andcloses the hot air passage P5. Further, a temperature adjusting mode canbe selected when the sliding door 16 b partially opens the hot airpassage P5 and bypass passage P6.

According to the present embodiment, the partition plate 25 partitionsthe portion between the inlet P0 to the air filter 14 of the air passageP of the air-conditioning unit 5 into right and left independentpassages P1 a, P1 b. This prevents that the passage cross-sectionrapidly increases at an area from the independent discharge ports 6 b, 7b of the air-blowing unit 4 to the introducing portion P1 of the airpassage P. In such a structure, when the air from the independentdischarge ports 6 b, 7 b of the air-blowing unit 4 flows into theair-conditioning unit 5, a rapidly reduced flow rate or a mutualinterference between the air from the discharge ports 6 b, 7 b can besuppressed. As a result, noise of the air conditioner 1 can be reducedduring operation. Further, since the air flowing through the evaporator15 is guided by the partition plate 25, an unevenness in the air flow isreduced and the heat transfer efficiency in the evaporator 15 isimproved.

For example, according to an experiment, as shown in FIG. 6, the airconditioner with the partition plate 25, 26 of the present embodiment(see a solid line in FIG. 6) has a noise reduction effect of almost 1dBA, compared to an air conditioner without partition plates 25, 26 of acomparative example (see a chain line in FIG. 6). In particular, aroundfrequency of 315 Hz, a noise reduction of about 1 to 3 dBA was observed.

FIG. 7 shows an air conditioner 1B according to another embodiment ofthe present invention, which is similar to the air conditioner shown inFIGS. 1 to 5.

FIGS. 8( a) and 8(b) show measured results of flow rate distribution(vector) at a measured face (a portion between the inlet P0 and the airfilter 14 of the air passage P) along the line B-B shown in FIG. 7.FIGS. 9( a) and 9(b) show measured results of static pressuredistribution at the measured face along the line B-B shown in FIG. 7.

Here, FIGS. 8( a) and 9(a) show flow rate distribution and staticpressure distribution of the air conditioner 1B having the partitionplate 25; and FIGS. 8( b) and 9(b) show flow rate distribution andstatic pressure distribution of the air conditioner without a partitionplate according to the comparative example.

Compared with the flow rate distribution (FIG. 8( b)) of the airconditioner 200 without a partition plate 25, according to the flow ratedistribution (FIG. 8( a)) of the air conditioner 1B having the partitionplate 25, a rapid reduction in flow rate of the air discharged from therespective fans 9, 10 and an interference between the discharged airfrom the both fans 9, 10 are reduced.

As described above, the above embodiments are effective to reduce noiseof the air conditioner during operation. Further, the air amount sentfrom the respective fans to the heat exchangers can be made even and theheat transfer efficiency in the heat exchangers can be improved.

Further, the above embodiments provide air conditioners having a simplestructure and reduced cost by simply providing the partition plate 25extending in the air flow direction, compared to the conventional art,in which air chambers, a porous bodies and a rib are required.

The above embodiments have the structure including the partition plate25 extending at an area between the inlet P0 of the air passage P andthe air filter 14 in the air flow direction and the other partitionplate 26 extending downstream the air mixing door device 16 in the airflow direction; however, it should be appreciated that the presentinvention is not limited to this example and the present invention mayhas a structure including the partition plate 25 without the otherpartition plate 26.

INDUSTRIAL APPLICABILITY

The present invention is applicable to not only a vehicular airconditioner but also other air conditioners for general machines orindustrial machines, for example.

1. An air conditioner comprising: an air-blowing unit including a casedefining a pair of independent scroll chambers, and a pair of fansrespectively provided in the scroll chambers; and an air-conditioningunit including an air-conditioning case defining an air passage whichair from the air-blowing unit flows through, an air-conditioningcomponent provided in the air passage and configured to condition airflowing therethrough, and a partition partitioning a portion of the airpassage between an inlet and the most upwind air-conditioning componentinto a pair of independent passages respectively communicating with thepair of scroll chambers.
 2. The air conditioner according to claim 1,wherein the partition is a plate member.
 3. The air conditioneraccording to claim 1, wherein the partition extends along a direction ofair blown from the air-blowing unit.
 4. The air conditioner according toclaim 1, wherein the partition extends along a direction which dischargeports of the pair of scroll chambers extend.
 5. The air conditioneraccording to claim 1, wherein the pair of independent passages extendperpendicular to an air flow direction in the most upwindair-conditioning component.
 6. An air conditioner comprising: anair-blowing unit including a case defining a pair of independent scrollchambers, and a pair of fans respectively provided in the pair of scrollchamber; and an air-conditioning unit including an air-conditioning casedefining an air passage which air blown from the air-blowing unit flowsthrough, and air-conditioning components provided in the air passage andconfigured to condition air therethrough, wherein the air passage of theair-conditioning unit includes an introduction passage between an inletand a cooling heat exchanger as one of the air-conditioning components,a passage portion between the cooling heat exchanger and an air mixingdoor device provided downstream the cooling heat exchanger as one of theair-conditioning components, a hot air passage provided downstream theair mixing door device and having a heating heat exchanger as one of theair-conditioning components therein, a bypass passage provideddownstream the air mixing door device and not having the heating heatexchanger therein, and an air mixing chamber provided at a confluenceportion of the hot air passage and the bypass passage to mix hot air andcool air, and wherein the air passage of the air-conditioning unit ispartitioned into a pair of independent passages that respectivelycommunicate with the pair of scroll chambers, and a confluence portioncommunicating the pair of independent passages is provided between thecooling heat exchanger and the air mixing door device.
 7. The airconditioner according to claim 6, the air mixing door device includes adoor case, an air mixing door slidably supported by the door case, apartition plate provided in the door case and partitioning a space inthe case so that the partitioned spaces respectively continue to thepair of independent passages.